In Part 1, I argued that dependability as a concept might be applied to organisations as well as to technical systems. In this post I will argue that both the organisational and technical levels should be modelled together as an interconnected system, and that test environments for dependability should include the simulation of organisational problems as well as technical problems.
Higher level organisational requirements cannot be considered in isolation from the underlying IT requirements. Organisational and IT system problems can interact in complex ways and such problems are common in real-world organisations. Therefore, these different levels need to be considered together. Such a multi-level system can be viewed as a socio-technical stack [Baxter & Sommerville 2011].
The different levels of requirements can be listed as follows:
- Specific organisational functionality requirements (e.g. medical workflows)
- Organisational dependability requirements (e.g. avoiding error)
- Specific IT requirements for the organisation (resources, networks etc.)
- IT dependability requirements (availability, security etc.)
Dependability requirements (2 and 4) may be more generic than 1 and 3. For example, all organisations will want to reduce error, but they may have different measures of what is acceptable. Requirements 3 and 4 can usually be satisfied by off-the-shelf components (but would need to be configured).
We assume that the software to satisfy the first set of requirements (1) has multiple users with different services. Such software is often called “enterprise application software”. In a health care system, users can be patients, clinicians or administrators. They access their own services in the system and they have specific actions available to them at particular stages in their workflow. For example, a patient could review their details or access records following a consultation. A clinician could request a test or respond to a symptom update from a patient.
Need for a test environment with simulation
To improve organisational resilience and dependability, it is important to develop new methods for detection and correction of organisational problems. To test these problem detection and recovery methods, it is useful to run simulated scenarios where human mistakes and IT failures can occur together. “Simulations” might involve people participating (as in a kind of role-playing game) or simulated computational agents [Macal 2016].
Examples of failure that might be simulated:
- mistakes (e.g. choosing the wrong test)
- administration failure: patient receives no response to a request (which should have a time limit).
- software failure: e.g. data interoperability issues.
- hardware failure
A test environment needs to be coupled with the iterative development of the system being tested. This would involve the development of increasingly complex problem-detection software in parallel with increasingly challenging scenarios. For example, the first version might involve simple errors that are easy to detect. Subsequent stages might involve increasingly more detailed work scenarios with more complex errors or failures. The more advanced stages might also involve real users in different roles (e.g. nursing students, medical students) and include time pressure.
Importance of agile and participatory design
In addition to developing safe systems, changing them safely is also important. So the development and test methodology needs to include change management. Agile software engineering is particularly important here, along with participatory design (co-design) methods. Ideally the system would be co-designed iteratively by the different users as they become aware of error-prone situations (such as cognitive overload) while participating in the evaluations. Design needs be informed by cognitive science as well as computer science.
In later posts, I plan to talk about the role of AI and decision support in organisational dependability.
- [Baxter & Sommerville 2011] Baxter G, Sommerville I. Socio-technical systems: from design methods to systems engineering Interacting with Computers, Volume 23, Issue 1, 1 January 2011, Pages 4–17
- [Macal 2016] Macal CM. Everything you need to know about agent-based modelling and simulation Journal of Simulation 10.